Novel prenyl 4-caranones

ABSTRACT

Novel prenyl 4-caranones of the general formula: ##STR1## wherein one R group represents a 3-methyl-2-butenyl group and the other a hydrogen atom 
     are useful olfactory agents in the preparation of fragrance materials.

This is a division, of application Ser. No. 96,721 filed Nov. 21, 1979U.S. Pat. No. 4,278,817.

The present invention is concerned with novel odorant substances.

The novel odorant substances provided by the present invention arecompounds of the general formula ##STR2## wherein one of the R symbolsrepresents the 3-methyl-2-butenyl group and the other represents ahydrogen atom.

The foregoing is accordingly intended to embrace3,7,7-trimethyl-3-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-4-one offormula Ia and3,7,7-trimethyl-5-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-4-one offormula Ib ##STR3## as well as all diastereoisomers of Ia and Ib whichare feasible having regard to the substituents on the six-membered ring.

The invention is also concerned with a process for the manufacture ofthe compounds of formula I.

This process comprises reacting 4-caranone of the formula ##STR4## witha prenyl halide.

Cis-4-caranone is preferably used as the starting material of formulaII.

Any prenyl halide can be used in the present process, but prenylchloride is preferred.

The reaction is preferably carried out in the presence of a stronginorganic base such as an alkali metal hydroxide (e.g. potassiumhydroxide), an alkaline earth metal hydroxide (e.g. calcium hydroxide),an alkali metal amide (e.g. sodamide) or an alkali metal hydride (e.g.sodium hydride). However, the reaction can also be carried out in thepresence of an organic base such as, for example, potassiumtert.butoxide.

The reaction can be carried out in the presence or absence of a solvent.Especially suitable solvents are aprotic or slightly polar solvents(e.g. dimethoxymethane, dimethoxyethane, diethyl ether ortetrahydrofuran).

The reaction temperature conveniently lies between approximately -20° C.and +50° C., preferably between 0° C. and 20° C. Lower temperatures areindustrially unpractical, while higher temperatures can readily lead toan undesired two-fold prenylation of the cis-4-caranene.

According to the process provided by the present invention there isobtained an isomer mixture of Ia and Ib, usually in the ratio of about80-90% of Ia and 20-10% of Ib.

Where desired, the separation of the isomer mixture (in which Iapredominantes) can be carried out in the customary manner, for example,by means of column chromatography or preparative gas chromatography. Aswill be evident from the following, the organoleptic properties of theisomers of I do not differ fundamentally so that it is preferred, oneconomical grounds especially, to use the isomer mixture.

On the basis of their organoleptic properties, the compounds of formulaI are excellently suited as odorant substances and this invention isconcerned with their use as odorant substances.

The compounds of formula I, especially the compound of formula Ia, arecharacterized by an interesting green note, which hitherto was absentfrom the palette of the perfumer, in that they combine together in onecompound at the same time facets of the flowery, fatty, herby and woodydirection and, moreover, display a long-lasting action in compositions.The evaluation of the olfactory properties of the individual componentsisolated from the mixture of I indicates that the odoriferousindividually of the ketone mixture I in accordance with the invention isdue predominantly to the compound Ia, although the isomers of formula Ibare not substantially different from Ia in their olfactory notes and, inparticular, are without any disturbing effect on the overall odour.

A separation of the isomer mixture is therefore, as mentioned earlier,uneconomical, and the mixture Ia/Ib obtainable in accordance with theinvention can advantageously be used as such for the manufacture ofodorant compositions.

Thus, I combines with numerous known natural or synthetic ingredients ofodorant compositions, whereby the range of natural ingredients canembrace not only readily-volatile but also semi-volatile anddifficulty-volatile substances and the range of synthetic ingredientscan embrace representatives from almost all classes of substances, aswill be evident from the following compilation:

Natural products such as angelica seed oil, tree moss absolute, bergamotoil, cardamom oil, acetylated cedarwood oil (e.g. Vertofix® IFF orCedartone® Givaudan), oak moss, pine-needle oil, galbanum oil, geraniumoil, jasmine absolute and its substitute, lavender oil, lavandin oil,patchouli oil, petitgrain oil (Paraguay), sandalwood oil, vetiver oil,ylang-ylang oil and lemon oil.

Alcohols such as cis-6-nonenol, linalool, citronellol, geraniol, naturalrhodinol, α-terpineol, phenylethyl alcohol, phenylpropyl alcohol andcinnamic alcohol.

Aldehydes such as 2,6-dimethyl-5-heptanal, decanal,methylnonylacetaldehyde, hydroxycitronellal, α-amylcinnamaldehyde,cyclamen aldehyde and p-tert.butyl-α-methyl-dihydro-cinnamaldehyde (e.g.Lilial® Givaudan).

Ketones such as α-ionone, acetylcedrene and p-methylacetophenone.

Esters such as cis-3-hexenyl acetate, cis-3-hexenyl benzoate, ethylacetoacetate, linanlyl acetate, geranyl acetate, terpenyl acetate,phenylethyl acetate, styrallyl acetate, p-tert.butyl-cyclohexyl acetate,4-[4-methyl-3-pentenyl]-cyclohex-3-en-1-yl-carbinyl acetate (e.g.Myraldyl acetate® Givaudan), cinnamyl formate, benzyl acetate, benzylsalicylate and amyl salicylate.

Lactones such as γ-undecalactone and coumarin.

Various additional substances frequently used in perfumery such as muskcompounds (musk ambrette, musk ketone, 12-oxa-hexadecanolide e.g. Musc175® Naarden), indole, p-methane-8-thiol-3-one, eugenol, acetaldehydepropylphenylethyl acetal and methyl 1-methylcyclodedecyl ether (e.g.Madrex® Givaudan).

The effect of freshness and naturalness which can be achieved by addingI to corresponding compositions, particularly those having flowerydirections, has proved itself to be especially surprising and valuable.This effect was unexpected having regard to the olfactory outflow of theindividual compound (constant flow over 48 hours, especiallygreen-woody, but without a fresh effect). In the case of a substancecontaining 15 carbon atoms it was much more likely that the oppositeeffect, namely a certain lasting heavyness, would be encountered.

It is also surprising that I in fruity-green notes, as shown in thefollowing Example 5 (melon), in spite of the individual green characterdoes not underline this green direction, but a nuancing whichintensively restores the fruit fresh with its sweetness comes to theforefront.

The compounds of formula I can accordingly be used in odorantcompositions in wide limits which, for example, can extend from 0.1% inthe case of detergents to 30% in the case of alcoholic solutions. Itwill, however, be appreciated that these values are not limiting values,since the experienced perfumer can also achieve effects with lowerconcentrations or can formulate novel complexes with higherconcentrations. The preferred concentrations vary between 0.5% and 25%.The odorant compositions prepared with I can be used for all kinds ofperfumed goods (e.g. Eau de Cologne, eau de toilette, extracts, lotions,creams, shampoos, soaps, salves, powders, toothpastes, mouth washes,deodorants, detergents, tobacco etc). In particular, the use ofcompositions containing I in soaps and detergents produces a verydesirable effect. Thus, by adding I to the compositions of Example 3hereinafter the odour of soap perfumes in this manner (1.2%) isconsidered to be very much fresher and more flowery in spite of theaddition of the woody-green-fatty compound I. This note also lasts overa longer period.

A washing powder having the following compositions:

Anion-active washing substance: 6%

Non-ionic washing substance: 5%

Soap powder: 7%

Sodium tripolyphosphate: 38%

Sodium silicate: 7%

Carboxymethylcellulose: 1%

Water: 3%

Sodium sulphate: 33%

is likewise very much stronger in its flowery-green olfactory note afterthe addition of, for example, 0.1%-0.5%, especially 0.2%, of the odorantcomposition of Example 3. Washing trials undertaken therewith show,compared with washing powder perfumed without the addition of I, asurprising result: not only in the case of hand washing (30° C.) butalso in the case of machine washing (60° C.) the superiority of thecomposition containing I shows itself in that this is strongly impartedto textiles washed therewith. The compounds of formula I are accordinglysurprisingly characterised not only by pure perfumistic effects, butalso by the capability of acting substantially themselves and also ofretaining this effect in combination with other odorant substances andat the same time of allowing the corresponding odorant substancemixtures to act substantively.

The following Examples illustrate the present invention:

EXAMPLE 1

120 g (0.79 mol) of cis-4-caranone are placed in a three-necked flaskprovided with a stirrer, a dropping funnel and a thermometer and cooledto 0° C. 110 g (1.67 mol) of powdered 85% potassium hydroxide are addedwhile stirring so that the temperature does not rise above 35° C. Aftercompletion of the addition, the mixture is stirred for a further 1 hourat 0° C. 84 g (0.8 mol) of prenyl chloride are then added dropwise sothat the temperature again rises to at most 35° C. After stirring atroom temperature for 12 hours, the mixture is poured on to ice,exhaustively extracted with diethyl ether, the combined ether extractsare washed neutral with water, dried over sodium sulphate andsubsequently formed freed from solvent. The crude product isfractionally distilled over a 50 cm packed column in vacuo (oil pump)and thus yields 60.5 g of olfactorily good material of boiling point 93°C./0.2 mmHg; n_(D) ²⁰ =1.4841. A main product as well as byproducteluted before and a byproduct eluted after this can be recognised in thegas chromatogram. The product mixture has the approximate composition11% (A), 83% (B) and 6% (C).

The isomers can be produced in practically pure form (above 95%) bypreparative gas chromatography and have the following spectralpropertes:

A

IR: 1700, 1452, 1376, 1205-1235 (broad), 1158, 1110, 1082, 1048, 1012,986, 962, 830 cm⁻¹.

NMR: 0.64 (m, 1H); 0.92 (m, 1H); 0.96 (s, 3H); 0.98 (d, J=7, 3H); 1.06(s, 3H); 1.20 (m, 1H); 1.62+1.73 (each s, each 3H); 2.0-2.5 (m, 5H); 5.1(m, 1H) δppm.

MS: 220(11,M+), 151(12), 137(9), 123(18), 109(21), 95(28), 91(26),79(27), 77(26), 69(30), 67(29), 55(29), 53(30), 41(100).

B

IR: 1698, 1452, 1408, 1376, 1348, 1292, 1205-1232 (broad) 1156, 1132,1120, 1108, 1086, 1048, 1014, 990, 964, 896, 858 cm⁻¹.

NMR: 0.63--1.2 (m below s, 2H); 0.88 (s, 3H); 0.91 (s, 3H); 1.07 (s,3H); 1.68+1.73 (each s, 6H); 2.03 (m, 1H); 2.28-2.52 (m, 4H); 5.02 (t,J=7 1H) δppm.

MS: 220(8,M+), 205(9), 151(25), 137(26), 123(100), 109(78), 95(32),81(37), 69(56), 55(20), 53(19), 41(68).

C

IR: 1670, 1448, 1378, 1354, 1322, 1282, 1205-1235 (broad), 1116, 1082,1040, 1012, 980, 910, 880 cm⁻¹.

NMR: 0.84-1.24 (m below d and s, 2H); 0.95 (d, J=6, 3H); 1.16 (s, 6H);1.36-1.53 (m, 2H); 1.66 (2 converging s, 6H); 1.78-2.52 (m, 4H); 5.00(t, J=6, 1H) δppm.

MS: 220(11,M+), 207(7), 152(47), 137(54), 123(24), 109(98), 95(74),82(31), 69(100), 55(33), 53(29), 41(92).

The main component B is identified unequivocally as3,7,7-trimethyl-3-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-4-one bythe ¹³ C-NMR-spectrum on the basis of the singlets at 19.3 ppm (as inthe cis-4-caranone) and 46.12 ppm (new).

On the other hand, the two components A and C have already in the ¹H-NMR-spectrum the characteristic doublet of the secondary methyl group,which is also observable in the cis-4-caranone, and are accordingly theisomeric3,7,7-trimethyl-5-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-4-ones.

EXAMPLE 2

30 ml of dimethoxymethane, previously purified over basic aluminumoxide, are placed in a 200 ml four-necked flask provided with a stirrer,two dropping funnels, a thermometer and a reflux condenser. 15 g (0.23mol) of powdered 85% potassium hydroxide are subsequently introducedwhile stirring and the entire content of the flask is cooled to 0° C. Atthis temperature there are thereupon simultaneously added dropwise fromtwo dropping funnels 11.4 g (0.075 mol) of cis-4-caranone and 7.8 g(0.0746 mol) of prenyl chloride within 2 hours so that the temperaturedoes not rise above +2° C. The mixture is stirred at room temperaturefor a further 2 hours, then poured on to ice and exhaustively extractedwith diethyl ether. The organic phase is washed neutral with water,dried over sodium sulphate and the solvent mixture is removed in arotary evaporator at 30° C./20 mmHg. The crude product (14.6 g) isfractionally distilled over a short Widmer column under a high vacuum.After a fore-run of 4.1 g of cis-4-caranone, I (7.6 g) can be distilledat 77° C./0.05 mmHg (n_(D) ²⁰ =1.4865). The product obtained is anisomer mixture of 85% Ia (B of Example 1) and 15% Ib (A of Example 1).

In the following Examples "I" denotes the isomer mixture of Ia/Ibobtained in Examples 1 and 2.

EXAMPLE 3 Flowery Base

    ______________________________________                                                             Parts by weight                                          ______________________________________                                        Propyleneglycol        200                                                    Benzyl acetate         100                                                    α-Ionone         100                                                    α-Amylcinnamaldehyde (substitute)                                                              100                                                    Citronellol            50                                                     p-Tert. butylcyclohexyl acetate                                                                      50                                                     Linalool               50                                                     Methyl 1-methylcyclododecyl ether                                                                    50                                                     Benzyl salicylate      30                                                     Vertofix® (IFF)    30                                                     Eugenol                30                                                     Cedartone® (acetylcedrene)                                                                       30                                                     Styrallyl acetate      20                                                     Terpenyl acetate       20                                                     Musc 174® (Naarden)                                                                              20                                                     Geraniol               20                                                     Linalyl acetate        20                                                     Ylang-ylang oil        10                                                     Acetaldehyde propylphenylethyl acetal                                                                10                                                     Hydroxycitronellal     5                                                      Methylnonylacetaldehyde (10% in ethyl                                         phthalate)             5                                                                             950                                                    ______________________________________                                    

If 50 parts of I are added to this flowery composition, which is in thedirection of hyacinth, then it becomes much more rounded-off, softer,more flowery and fresher. The ionone note is very pleasantly enveloped.In the bottom a freesia note surprisingly arises from the hyacinth. Thepowdery-woody note which appears in the original base is masked by theflowery note. The fresh note lasts over a period of 24 hours.

EXAMPLE 4 Flowery Composition in the Direction of Lilac

    ______________________________________                                                              Parts by weight                                         ______________________________________                                        Terpineol               260                                                   Hydroxycitronellal      200                                                   Phenylethyl alcohol     160                                                   Cinnamic alcohol (substitute)                                                                         100                                                   Phenylpropyl alcohol    100                                                   Cinnamyl formate        20                                                    Geranyl acetate         10                                                    Musk ketone             10                                                    Jasmine (substitute)    10                                                    Eugenol                 5                                                     Indole (10% in ethyl alcohol)                                                                         5                                                     p-Menthane-β-thiol-3-one (10% in                                         propyleneglycol)        5                                                     p-Methylacetophenone    5                                                     C-10 aldehyde (10% in propyleneglycol)                                                                5                                                     δ-Undecalactone   5                                                                             900                                                   ______________________________________                                    

This base, prepared exclusively from synthetic substances, leaves behindthe impression of a still very synthetic-chemical lilac. After theaddition of 100 parts of I to this base, the resulting base has anextraordinary natural note and is now reminiscent of fresh floweringlilac.

EXAMPLE 5 Fruity Perfume Base in the Direction of Melon

    ______________________________________                                                             Parts by weight                                          ______________________________________                                        Propyleneglycol        180                                                    Linalyl acetate        120                                                    Myraldyl acetate® (Givauden)                                                                     120                                                    Hexenyl benzoate       100                                                    Cyclamen aldehyde      80                                                     2,6-Dimethyl-5-heptenal (10% in ethyl                                         alcohol)               60                                                     Ethyl acetoacetate     60                                                     Cis-6-nonenol (10% in ethyl alcohol)                                                                 40                                                     Lilial® (Givaudan) 20                                                     Hexenyl acetate (10% in alcohol)                                                                     20                                                                            800                                                    ______________________________________                                    

If 200 parts of I are added to this fruity base, then these results fromthe original fruity-green melon, which has a basic note reminiscent ofmelon skin, a much sweeter and rounded-off melon note. The fruit fleshnote is pleasantly underlined.

EXAMPLE 6 Chypre Base in the Direction of Mens Cologne

    ______________________________________                                                              Parts by weight                                         ______________________________________                                        Propyleneglycol         200                                                   Bergamot oil            100                                                   Methyl 1-methylcyclododecyl ether                                                                     100                                                   Hydroxycitronellal      80                                                    Musc 174® (Naarden) 60                                                    Patchouli oil           50                                                    Pine needle oil         50                                                    Citronellol             40                                                    Tree moss absolute (50% in propylene-                                         glycol)                 30                                                    Galbanum oil            30                                                    Lemon oil               20                                                    Petitgrain oil (Paraguay)                                                                             20                                                    Cedartone® (IFF)    20                                                    Cardamom oil            5                                                     Angelica seed oil       5                                                     α-Ionone          40                                                    Linalool                50                                                                            900                                                   ______________________________________                                    

If 100 parts of I are added to this base, which can be used for meansCologne directions, then the thusobtained base is much lighter, moreflowery and softer. I very advantageously envelops the harsh, prominentgalbanum note of the original composition and forms, together with theionone-musk note, a novel complex.

EXAMPLE 7 Perfume Compositions in the Direction of Fougere

    ______________________________________                                                             Parts by weight                                          ______________________________________                                        Lavender oil           200                                                    Amyl salicylate        200                                                    Coumarin               100                                                    Oak moss absolute (Yugoslavian)                                                                      80                                                     Geranium oil (Bourbon) 60                                                     Bergamot oil           60                                                     Musk ambrette          60                                                     Petitgrain oil (Paraguay)                                                                            40                                                     α-Ionone         40                                                     Vetiver oil (Bourbon)  40                                                     Sandalwood oil         40                                                     Patchouli oil          20                                                     α-Amylcinnamaldehyde (substitute)                                                              20                                                     Eugenol                20                                                                            980                                                    ______________________________________                                    

If 20 parts of I are added to this Fougere base, then the oak moss noterecedes in the novel compositions. The addition confers more softness tothe novel base. Moreover, the lavender note is very pleasantlyunderlined, and this results in the novel composition having asubstantially fresher impression.

EXAMPLE 8 Perfume Base in the Direction of Rose

    ______________________________________                                                             Parts by weight                                          ______________________________________                                        Phenylethyl alcohol    400                                                    Citronellol            180                                                    Geraniol               150                                                    Linalool               100                                                    α-Ionone         50                                                     Hydroxycitronellal     50                                                     Phenylethyl acetate    30                                                     Benzyl acetate         20                                                                            980                                                    ______________________________________                                    

If 20 parts of I are added to this conventional rose base, then the rosycharacter is substantially altered; whereas the original basecorresponds to a red rose, a yellow rose is generated by the addition.

EXAMPLE 9 Perfume Base in the Direction of Lily of the Valley

    ______________________________________                                                             Parts by weight                                          ______________________________________                                        Hydroxycitroellal      430                                                    Rhodinol extra         350                                                    Linalool               80                                                     α-Amylcinnamaldehyde                                                                           50                                                     Sandalwood oil         50                                                     Ylang-ylang oil        20                                                                            980                                                    ______________________________________                                    

If 20 parts of I are added to this lily of the valley base, then thetypical fresh-green character of this flower is brought to theforefront. I confers much more naturalness to the base.

I claim:
 1. A fragrance composition comprising an olfactorily effectiveamount of a compound of the general formula ##STR5## wherein one of theR symbols represents a 3-methyl-2-butenyl group and the other representsa hydrogen atom, and at least one other fragrance material.
 2. A methodfor improving the odor of a fragrance composition which comprises addingthereto an effective amount of a compound of the general formula##STR6## wherein one of the R symbols represents a 3-methyl-2-butenylgroup and the other represents a hydrogen atom.
 3. The method of claim 2wherein there is added an effective amount of a mixture consistingessentially of about 85%,3,7,7-trimethyl-3-(3'methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-3-one andabout 15%3,7,7-trimethyl-5-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-3-one. 4.A composition according to claim 1 wherein I is between about 80 to 90%3,7,7-trimethyl-3-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-4-one andbetween about 20% to 10%3,7,7-trimethyl-5-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptane-4-one.5. A composition according to claim 1 wherein I is 85%3,7,7-trimethyl-3-(3'methyl-2'-butenyl)-bicyclo[4.1.0]heptan-4-one and15% 3,7,7-trimethyl-5-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]heptan-4-one.6. A composition according to claim 1 wherein I is3,7,7-trimethyl-3-(3'methyl-2'-butenyl)-bicyclo-[4.1.0]-heptan-4-one. 7.A composition according to claim 1 wherein I is3,7,7-trimethyl-5-(3'methyl-2'-butenyl)-bicyclo-[4.1.0]-heptan-4-one. 8.The method of claim 2 wherein there is added an effective amount of amixture consisting essentially of between about3,7,7,7-trimethyl-3-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-4-oneand between about 10-20%3,7,7-trimethyl-5-(3'-methyl-2'-butenyl)-bicyclo[4.1.0]-heptan-4-one.